JP6524689B2 - Continuous casting equipment - Google Patents

Description

  The present invention relates to a continuous casting apparatus.

  In the twin-roll continuous casting method of nonferrous metals or their alloys, the molten metal of the material is lowered to below the liquidus temperature to be in a semi-solid state before pouring it between the rolls, and the resulting semi-solid material is quenched between the rolls Techniques for coagulation are known. According to such a technique, it is possible to suppress the growth of crystal grains to refine the structure, and to obtain a thin plate of high quality.

As such a twin roll continuous casting method, in Non-Patent Document 1 and Non-Patent Document 2, heat is taken away by flowing molten aluminum alloy on a sloped flat plate, and then it is poured into twin rolls and cooled to obtain a rapidly solidified structure. It is disclosed to obtain.
Moreover, in patent document 1, after preventing a metallic material from solidifying below the liquidus temperature using a stirring rod, it has sent in to the twin roll.

Japanese Patent Application Laid-Open No. 9-296232

Hideto Harada, Toshio Haga, Shin-ichi Nishida, Hisaki Watari "Twin-roll casting and formability of Al-25% Si alloy sheet" Proceedings of the Japan Society of Mechanical Engineers (A) Vol. 79 (213-8), p 78- 82 Takuya Yamashiki, Toshio Haga, Shinji Kumai, Hisaki Watari "Effects of Roll Surface on Aluminum Alloy Plates Produced by High-speed Twin Roll Caster," Proceedings of the Japan Society of Mechanical Engineers (A) Vol. 79, No. 804 (213-8) , P92-96

However, the above conventional methods have the following problems.
Although the casting methods disclosed in Non-Patent Document 1 and Non-Patent Document 2 can be produced in small quantities, the area exposed to air is large, so it is particularly desirable to cast metal materials highly reactive with the outside air. The compounds may be mixed inside the material to reduce the product quality. Moreover, when attempting to continuously cast a wide plate material, it is difficult to flow the material uniformly into the twin rolls.
Even in the casting method disclosed in Patent Document 1, when attempting to continuously cast a wide plate material, it is difficult to flow the material uniformly into the twin rolls.

  The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a continuous casting apparatus capable of reliably pouring pre-cooled molten metal into twin rolls and therefore applicable to continuous casting of a wide plate material. There is.

  The continuous casting apparatus of the present invention comprises a melting furnace for melting non-ferrous metals or alloys thereof, and a twin roll comprising a pair of rolls for cooling and continuously casting non-ferrous metals or alloys thereof supplied from the melting furnace. And a cooling device for supplying a cooled material obtained by cooling the molten metal supplied from the melting furnace between the pair of rolls above the gap between the pair of rolls. I assume.

  Further, in the continuous casting apparatus, the cooling device is formed to have a cooling / stirring portion for cooling the molten metal and stirring the molten metal by disturbing the flow of the molten metal.

  In the continuous casting apparatus, the nonferrous metal or the alloy thereof is a highly reactive nonferrous metal or the alloy thereof, and a cylindrical molten metal reservoir for storing the molten metal is provided on the cooling device, and the melting furnace and the melting furnace A melt supply pipe for supplying the melt to the melt storage is provided between the melt storage and the melt supply pipe, and the discharge port is positioned below the surface of the melt held in the melt storage. It is characterized by

  In the above continuous casting apparatus, the non-ferrous metal is magnesium.

  According to the continuous casting apparatus of the present invention, the cooling device for supplying the cooled material obtained by cooling the molten metal supplied from the melting furnace between the pair of rolls is provided between the pair of rolls. The molten metal (coolant) pre-cooled by the cooling device can be reliably poured into the twin roll consisting of a pair of rolls, and therefore, it can be applied to the continuous casting of a wide plate material.

It is a side view showing typically a 1st embodiment of a continuous casting device concerning the present invention. It is a top view of a twin roll. It is principal part sectional drawing of FIG. It is a top view of a molten metal storage. (A), (b) is a longitudinal cross-sectional view for demonstrating schematic structure of a cooling device.

Hereinafter, the continuous casting apparatus of the present invention will be described in detail with reference to the drawings. In the following drawings, the scale of each member is appropriately changed in order to make each member have a recognizable size.
FIG. 1 is a side view schematically showing a first embodiment of a continuous casting apparatus according to the present invention, and reference numeral 1 in FIG. 1 is a continuous casting apparatus. The continuous casting apparatus 1 comprises a melting furnace 2 for melting nonferrous metals or alloys thereof, and a twin roll 3 comprising a pair of rolls 3a for cooling and continuously casting nonferrous metals or alloys thereof supplied from the melting furnace 2. And a cooling device 19 disposed on the twin roll 3, a molten metal reservoir 4 disposed on the cooling device 19, and a tower portion 5 disposed on the molten metal reservoir 4 .

  Melting furnace 2 is a furnace for melting a non-ferrous metal or an alloy thereof to be subjected to continuous casting, and has a heating device (not shown) capable of heating to a temperature exceeding the melting point of the material to be melted. Further, the melting furnace 2 is provided with a lid portion 2a for airtightly closing the inside thereof. And the inert gas is supplied to the inside of the melting furnace 2 and filled with the inert gas to prevent the molten nonferrous metal or its alloy, that is, the molten metal from reacting in contact with oxygen (air). 6 are connected.

  The inert gas supply device 6 has an inert gas supply source 7 and a first inert gas supply pipe 8, and the inert gas supplied from the inert gas supply source 7 is a first inert gas. The molten metal 50 in the melting furnace 2 is supplied above the surface 50 a of the molten metal 50 by the supply pipe 8. By covering the surface 50a of the molten metal 50 with the inert gas in this manner, the molten metal 50 is prevented from coming into contact with oxygen (air) and reacting.

  Further, in the melting furnace 2, a molten metal supply pipe 9 is connected to the lid portion 2a, and the melting furnace 2 derives the molten metal 50 through the molten metal supply pipe 9 and sends it to the molten metal reservoir 4 on the roll 3a. It is configured. The molten metal supply pipe 9 is provided so as to penetrate the lid 2 a, and the suction port 9 a thereof is disposed sufficiently below the surface 50 a of the molten metal 50 in the melting furnace 2. As a result, the molten metal supply pipe 9 sucks in the molten metal 50 which is not located in the surface 50a or its vicinity, that is, the molten metal 50 which does not contain a reactant formed by touching oxygen (air).

  In the present embodiment, the above-described inert gas supply device 6 is used as a molten metal supply device that causes the molten metal 50 to flow into the molten metal supply pipe 9 and sends the molten metal 50 to the molten metal reservoir 4 on the roll 3a. By pressurizing the surface 50 a of the molten metal 50 in the melting furnace 2 by the inert gas supply device 6, the molten metal 50 can be made to flow into the suction port 9 a of the molten metal supply pipe 9 and sent to the molten metal reservoir 4. The molten metal supply device for sending the molten metal 50 in the melting furnace 2 to the molten metal reservoir 4 through the molten metal supply pipe 9 may be formed by, for example, a known pressure transfer pump having an electric motor instead of the inert gas supply device 6 Good.

The inert gas supply source 7 of the inert gas supply device 6 includes a gas cylinder or a gas tank for storing an inert gas such as sulfur hexafluoride (SF ₆ ) or argon (Ar), and a pressure feeding provided as necessary. It is formed by a pump.
The inert gas supply device 6 is provided with a second inert gas supply pipe 11 separately from the first inert gas supply pipe 8. The second inert gas supply pipe 11 is also connected to the inert gas supply source 7 so as to supply an inert gas to a tower portion 5 described later.

  The twin roll 3 is disposed in a state where the pair of rolls 3a are close to each other horizontally and at the same height with a predetermined gap.

  Moreover, as shown in FIG. 2 which is the top view in the twin roll 3, the weir 12 is provided in the end surface of a roll longitudinal direction, respectively. These weirs 12 seal so that the molten metal 50 supplied on the gap between the pair of rolls 3a does not flow out other than in the casting direction.

  In addition, on the downstream side of the twin roll 3, a winder (not shown) for winding a plate material continuously cast by the pair of rolls 3a is provided.

  The molten metal reservoir 4 is disposed immediately above the gap between the pair of rolls 3a constituting the twin roll 3 and in the vicinity thereof, and holds the molten metal 50 as shown in FIG. It has a cylindrical shape with a through hole 13 to allow it to flow down. Here, as shown in FIG. 4 which is a plan view of the molten metal reservoir 4, the molten metal reservoir 4 has a plan view shape in which the direction along the rotation axis O direction of the roll 3a is a long side and is orthogonal to this long side It is formed in the rectangle which makes the direction to be a short side. The length of the long side in the plan view shape is formed to be substantially equal to the length in the rotation axis direction of the roll 3a. The length of the short side in the plan view shape is appropriately determined by the diameter of the roll 3a, the rotation speed, and the like.

  As shown in FIG. 3, a molten metal supply pipe 9 is connected to the side of one long side of the molten metal reservoir 4 so as to penetrate therethrough. The molten metal supply pipe 9 is formed to be curved such that its front end faces downward, and a header 14 is further provided at its front end. The header 14 is formed to be elongated corresponding to the opening shape of the through hole 13 as shown in FIG. As described above, by providing the header 14 corresponding to the opening shape of the through hole 13 at the tip of the molten metal supply pipe 9, the molten metal 50 can be uniformly supplied to the entire area of the through hole 13. The molten metal reservoir 4, the tower portion 5, the cooling device 19, and the like are heated by a heating coil, a heat transfer wire, or the like so as to prevent the metal from solidifying at that location and maintain the liquid state. Only the roll 3a has a structure in which the molten metal solidifies at a low temperature.

  Further, in the present embodiment, a straightening device 53 (a straightening plate, a diverting box, or the like is provided along the short side direction in the through hole 13 so that the molten metal 50 supplied in this manner uniformly flows to the roll 3a side. ) Are erected in the vertical direction. Thereby, the molten metal 50 supplied from the header 14 uniformly flows down to the roll 3 a side as the flow is adjusted by the flow straightening plate 53.

The header 14 is provided with a large number of openings on the lower surface thereof, and hence these openings become the substantial discharge ports 9b of the molten metal supply pipe 9 as shown in FIG.
The molten metal 50 is supplied to the molten metal reservoir 4 from the molten metal supply pipe 9 in the preliminary operation of the continuous casting apparatus 1 so that the molten metal surface 50 b is above the discharge port 9 b of the molten metal supply pipe 9. Is stored. Therefore, the discharge port 9 b of the molten metal supply pipe 9 is disposed below the surface 50 b of the molten metal 50 stored in the molten metal reservoir 4 during the main operation in which the continuous casting is performed.

  A tower portion 5 is disposed on such a molten metal reservoir 4. The tower portion 5 is formed of a cylindrical portion 15 having a rectangular shape in plan view, which is the same as the molten metal reservoir 4, and a buffer portion 16. The cylindrical portion 15 is a cylinder whose plan view shape is substantially the same as the plan view shape of the molten metal reservoir 4 and is formed to be sufficiently higher in height than the molten metal reservoir 4 and has the same planar view shape as the molten metal reservoir 4 A through hole 17 is provided. The through hole 17 is formed in the same opening shape as the through hole 13 of the molten metal reservoir 4 and is in communication with the through hole 13 and disposed continuously. Therefore, the molten metal 50 stored in the molten metal reservoir 4 has its molten metal surface 50 b ascends the through holes 13 of the molten metal reservoir 4 and reaches the inside of the through holes 17 of the cylindrical portion 15.

  The buffer portion 16 is disposed at the upper end of the cylindrical portion 15 and airtightly closes the upper end side opening of the through hole 17 of the cylindrical portion 15 and has a space portion 18 communicating with the through hole 17 of the cylindrical portion 15 inside. doing. The buffer portion 16 has a length in the short side direction, that is, a length in the direction orthogonal to the rotation axis O of the roll 3a is longer than that of the cylindrical portion 15. Therefore, the area of the space 18 in plan view is a penetration The area is larger than the area of the hole 17 in plan view. As a result, the amount of the molten metal 50 supplied and stored in the molten metal storage 4 rapidly increases, and the molten metal 50 flows into the space 18 of the buffer section 16 even if the surface 50b of the molten metal rises rapidly. The sudden rise of the surface 50b can be suppressed.

  In addition, the second inert gas supply pipe 11 is connected to the upper lid 16 a of the buffer section 16. The second inert gas supply pipe 11 is connected to the inert gas supply source 7 shown in FIG. 1 to send the inert gas supplied from the inert gas supply source 7 into the space 18 of the buffer section 16. . The inert gas sent into the space 18 covers the surface 50b of the molten metal 50 located in the through hole 17 of the cylinder 15, thereby preventing the molten metal 50 from contacting with oxygen (air) and reacting It is done. Further, a pressure control valve 56 is provided on the upper lid 16 a of the buffer section 16 so that the pressure in the buffer section 16, that is, the internal pressure on the surface 50 b of the molten metal 50 can be adjusted. Further, a pressure gauge 57 is provided on the upper lid 16a of the buffer section 16, whereby the pressure in the buffer section 16 (the internal pressure on the surface 50b of the molten metal 50) can be detected.

  The extrusion pressure of the molten metal 50 stored in the molten metal reservoir 4 can be controlled by the inert gas supply device 6 having the second inert gas supply pipe 11 and the inert gas supply source 7.

  Further, the molten metal supply device (inert gas supply device 6) having the first inert gas supply pipe 8 and the inert gas supply source 7 described above also extrudes the molten metal 50 stored in the molten metal reservoir 4 The pressure can be controlled. A molten metal supply apparatus (inert gas supply apparatus 6) including such a first inert gas supply pipe 8 and an inert gas supply source 7, a second inert gas supply pipe 11, and an inert gas supply The molten metal pressure control means according to the present invention is configured to control the extrusion pressure of the molten metal 50 stored in the molten metal reservoir 4 by one or both of the inert gas supply device 6 having the source 7 and Ru.

  The cooling device 19 is disposed below the molten metal reservoir 4 and above the gap between the pair of rolls 3a as shown in FIG. The cooling device 19 is a cylindrical body whose rectangular shape in plan view is substantially the same as that of the molten metal reservoir 4 and therefore has a through hole 20 of the same planar shape as the molten metal reservoir 4. The through hole 20 is formed in the same opening shape as the through hole 13 of the molten metal reservoir 4, is in communication with the through hole 13, and is disposed continuously. Therefore, the molten metal 50 stored in the molten metal storage 4 flows down through the through hole 13 of the molten metal storage 4, passes through the through hole 20 of the cooling device 19, and is provided on the gap between the pair of rolls 3 a .

  A plurality of cooling pipes 21 are disposed in the cooling device 19 between the side walls forming the short side in the plan view shape, that is, along the direction of the rotation axis O of the roll 3a. The cooling pipe 21 cools the molten metal 50 passing through the through hole 20 by letting a refrigerant such as air pass therethrough. Further, the cooling pipes 21 are arranged in four upper and lower stages as shown in FIG. 3, for example, so that the cooling pipes 21 relatively collide with the molten metal 50 flowing down from the top and disturb the flow. Thus, the cooling pipe 21 functions as a cooling / stirring portion in the present invention by being disposed so as to stir the molten metal 50 by disturbing the flow of the molten metal 50.

  The cooling by the cooling device 19 is performed by the cooling pipe 21 constituting the cooling / stirring portion, but instead, a flat plate-like cooling plate (fin) made of a material having high heat conductivity such as copper or a solid It may be performed using a cooling rod. In this case, the cooling plate and the cooling rod are extended from the side wall of the cooling device 19 and the extending portion is cooled by another cooling device. By thus cooling the extension portion, cold heat can be transferred into the through holes 20 of the cooling device 19 by heat conduction, and the molten metal 50 in the through holes 20 can be cooled.

  Even when a cooling plate or rod is used, the flow is disturbed by causing the cooling plate or rod to collide with the molten metal 50 flowing down from the top, similarly to the cooling pipe 21 shown in FIG. Arrange to stir. That is, the cooling plate and the cooling rod function as a cooling stirring unit. As arrangement | positioning of the cooling pipe 21, a cooling plate, and a cooling rod, the arrangement | positioning as shown, for example to FIG. 5 (a), (b) besides the arrangement | positioning shown in FIG. 3 is employable.

In FIG. 5A, a fin-shaped cooling plate 22 is integrally attached to the cooling pipe 21 and the molten metal 50 flowing downward from above is stirred by the cooling pipe 21 and simultaneously cooled by the cooling pipe 21 and the refrigerant passing therethrough. The molten metal 50 is cooled by the cooling plate 22. In this example, a solid cooling rod may be used instead of the cooling pipe 21. Further, in this example, a rectifying effect of rectifying the molten metal 50 by the cooling plate 22 is also obtained.
In FIG. 5B, the cooling pipes with large diameter are arranged in a zigzag shape, and the gap between the cooling pipes 23 is narrowed to improve the cooling efficiency and the stirring efficiency. Also in this example, instead of the cooling pipe 23, a solid cooling rod may be used. Arrows in FIGS. 5A and 5B indicate the flow of the molten metal 50.

  The cooling of the molten metal 50 by the cooling device 19 is performed at a temperature slightly lower than the melting point of the material to be subjected to continuous casting, in this embodiment, the magnesium alloy. By setting the temperature to a temperature lower than the melting point in this way, the molten metal 50 is pre-cooled to solidify when passing through the cooling device 19, that is, immediately before being cooled in contact with the peripheral surfaces of the pair of rolls 3 a. . However, since the molten metal 50 is agitated and disturbed in its flow by the cooling pipe 21 or the like of the cooling device 19, the fluidity is not completely lost even if it is cooled to a temperature slightly lower than the melting point, and it becomes semisolidified.

  Then, after the molten metal 50 is cooled to the semi-solidified state as described above, as shown in FIG. 3, the semi-solids 51 are provided between the pair of rolls 3a and continuously cast. Since the molten metal 50 is semi-solidified immediately before being provided between the pair of rolls 3a, the growth of crystal grains when solidified between the rolls 3a is suppressed, and the product quality is improved. If the crystal grains grow large, for example, the strength of the obtained plate material may be reduced, and the desired quality characteristics may not be obtained.

  In order to secure the fluidity of the molten metal 50 (semi-solid 51) which has been semi-solidified by cooling, a heating device is provided on the side wall of the cooling device 19 and the side wall is higher than the cooling temperature by the cooling pipe 21 etc. The side wall may be heated to a temperature.

  The cooling device 19 is disposed at a slight gap from the circumferential surface of the pair of rolls 3a. The molten metal 50 (semi-solids 51) is cooled by the cooling device 19 and semi-solidified, and then immediately cooled on the peripheral surface of the pair of rolls 3a, so it hardly reacts with the outside air (oxygen). It is continuously cast without being. However, in order to prevent the reaction on the pair of rolls 3a, the inert gas is supplied from the above-mentioned inert gas source 7 to the pair of crucibles 12 through the third inert gas supply pipe (not shown). The supply may be performed, and an inert atmosphere may be provided on the gap between the pair of rolls 3a. By thus setting the inert atmosphere on the gap, it is possible to reliably prevent the semisolid 51 flowing out of the cooling device 19 from reacting on the gap.

  The molten metal pressure control means described above controls the extrusion pressure of the molten metal 50 stored in the molten metal reservoir 4 so that the molten metal 50 (semi-solidified material 51) which has flowed out of the cooling device 19 is on the circumferential surface of the pair of rolls 3a. Control the pressure applied. As the pressing pressure is increased to a preset high pressure, the heat transfer coefficient from the roll 3a to the molten metal 50 is improved, the cooling efficiency is improved, and the heat transfer coefficient becomes even over the entire peripheral surface of the roll 3a. Preference is given to solidification taking place uniformly and less unevenness of product quality.

  When the inert gas supply device 6 having the second inert gas supply pipe 11 and the inert gas supply source 7 is made to function as the molten metal pressure control means, the buffer section is provided by the second inert gas supply pipe 11 Adjust the amount of inert gas supplied into 16. Thereby, the pressure in the buffer section 16, that is, the internal pressure on the surface 50b of the molten metal 50 can be controlled, and the extrusion pressure of the molten metal 50 in the molten metal reservoir 4 to which this internal pressure is applied can be controlled. Such control of the internal pressure can be performed with high accuracy by using the pressure gauge 57 and the pressure control valve 56 provided in the buffer unit 16. Therefore, the pressing pressure of the molten metal 50 (semi-solid material 51) on the circumferential surface of the pair of rolls 3a can be precisely controlled.

  When the molten metal supply apparatus (inert gas supply apparatus 6) including the first inert gas supply pipe 8 and the inert gas supply source 7 functions as the molten metal pressure control means, the first inert gas The amount of inert gas supplied to the melting furnace 2 is adjusted by the gas supply pipe 8, and the amount of molten metal 50 sent to the molten metal reservoir 4 via the molten metal supply pipe 9 is controlled. Thereby, the surface 50b of the molten metal 50 in the tower 5 can be moved up and down, and the head pressure of the molten metal 50 stored in the tower 5, the molten metal reservoir 4 and the cooling device 19 can be controlled. Therefore, the pressing pressure of the molten metal 50 (semi-solid material 51) on the circumferential surface of the pair of rolls 3a can be precisely controlled.

  In order to perform continuous casting by the continuous casting apparatus 1 having such a configuration, first, a magnesium alloy is melted in the melting furnace 2. Then, the obtained molten metal 50 is supplied into the through hole 13 of the molten metal reservoir 4 by the molten metal supply pipe 9. The molten metal 50 supplied to the molten metal reservoir 4 by the molten metal supply pipe 9 is stored so as to be positioned on the molten metal surface 50b by supplying more molten metal 50 than the molten metal 50 flowing down. As a result, the discharge port 9b of the molten metal supply pipe 9 is positioned below the surface 50b of the molten metal 50, and the molten metal 50 supplied in an airtight state from the melting furnace 2 by the molten metal supply pipe 9 causes a reaction. The molten metal 50 forming the easy molten metal surface 50 b is left as it is at or near the molten metal surface 50 b, flows downward from the molten metal surface 50 b and flows down to the cooling device 19 through the through holes 13.

  Thus, when the molten metal 50 is supplied into the molten metal reservoir 4, the molten metal supply device (not including the first inert gas supply pipe 8 and the inert gas supply source 7 described above) is provided. The extrusion pressure of the molten metal 50 stored in the molten metal reservoir 4 is determined by the inert gas supply unit 6 having the active gas supply unit 6) or the second inert gas supply pipe 11 and the inert gas supply source 7. Control. As a result, as described above, the pressing pressure of the semi-solids 51 against the circumferential surface of the pair of rolls 3a is precisely controlled to a preset high pressure. Further, since the molten metal surface 50b of the molten metal 50 is positioned in the cylindrical portion 15 of the tower portion 5, a sufficiently large head pressure is applied to the molten metal 50 stored in the molten metal reservoir 4, and therefore the semisolidification The pressing pressure of the object 51 is stable without significant fluctuation.

  The molten metal 50 which has flowed down to the cooling device 19 is semi-solidified by being cooled by the cooling pipe 21 and the like and stirred as described above. Then, the formed semi-solid material 51 is guided to the gap between the pair of rolls 3a which circulates. The semisolid 51 guided to the gap in this manner is pressed against the circumferential surface of the roll 3a with a precisely controlled pressing pressure, solidified by being passed through the gap between the rolls 3a, and continuously cast, Is formed. Therefore, the plate material obtained as a product or a semi-finished product can be obtained by winding up the obtained plate material and then cutting the ears on both sides to form desired dimensions.

  According to the continuous casting apparatus 1 of the present embodiment, a cooled material (semi-solidified material 51) obtained by cooling the molten metal 50 supplied from the melting furnace 2 is placed between the pair of rolls 3a between the pair of rolls 3a. Since the cooling device 19 for supplying between is provided, the semi-solids 51 pre-cooled by the cooling device 19 can be reliably poured into the twin roll 3 consisting of the pair of rolls 3a, so that the wide plate material is also continuous Casting can be done easily.

  Further, the cooling device 19 has a cooling / stirring portion (cooling tube 21) for stirring the molten metal 50 by cooling the molten metal 50 and disturbing the flow of the molten metal 50. Can be semi-solidified immediately before being provided between the pair of rolls 3a, so that the growth of crystal grains during solidification between the rolls 3a can be suppressed and the product quality can be improved.

  Further, a molten metal reservoir 4 for storing the molten metal 50 is provided on the cooling device 19, a molten metal supply pipe 9 is provided between the melting furnace 2 and the molten metal reservoir 4, and the discharge port 9 b of the molten metal supply pipe 9 is Since the molten metal 50 is positioned below the molten metal surface 50b of the stored molten metal 50, the molten metal 50 forming the molten metal surface 50b susceptible to reaction can be left as it is at or near the molten metal surface 50b. The molten metal 50 can be prevented from flowing between the rolls 3a and being subjected to continuous casting. Therefore, without using huge equipment, it is possible to prevent the reaction of the molten metal 50 before casting and to prevent the deterioration of the continuous cast product obtained.

  In particular, even when magnesium or its alloy having high reactivity is continuously cast, the reaction can be surely prevented, and therefore, it is possible to manufacture a light and high strength magnesium-based sheet material with good quality.

  Further, since the molten metal pressure control means is provided, a pair of rolls of the semi-solid material 51 which has flowed out of the cooling device 19 by controlling the extrusion pressure of the molten metal 50 stored in the molten metal reservoir 4 by the molten metal pressure control means. The pressing pressure on the circumferential surface of 3a can be controlled. Therefore, the pressure transfer is performed by setting the pressing pressure to a previously set high pressure, and the heat transfer coefficient from the roll 3a to the molten metal 50 is increased to improve the cooling efficiency, and the heat transfer coefficient is used as the circumferential surface of the roll 3a. It is possible to make the whole uniform and to cause solidification uniformly and to reduce unevenness of product quality.

  In the case where a molten metal supply device is used which adjusts the amount of molten metal 50 supplied to the molten metal reservoir 4 by the molten metal supply pipe 9 as the molten metal pressure control means and raises and lowers the molten metal surface 50b of the molten metal 50 in the tower portion 5 Since the water head pressure of the molten metal 50 can be controlled well, the pressing pressure of the semi-solids 51 on the circumferential surface of the pair of rolls 3a can be precisely controlled.

  In the case where an inert gas is introduced above the surface 50b of the molten metal 50 in the tower 5 as the molten metal pressure control means, and the inert gas supply device 6 is used to adjust the extrusion pressure in the tower 5. The internal pressure of the molten metal 50 on the surface 50b can be controlled by adjusting the amount of the inert gas supplied by the second inert gas supply pipe 11, and thereby the inside of the molten metal reservoir 4 to which the internal pressure is applied. The extrusion pressure of the molten metal 50 can be controlled. Therefore, the pressing pressure of the semi-solids 51 against the circumferential surface of the pair of rolls 3a can be precisely controlled.

The present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, although the twin rolls 3 are configured such that the pair of rolls 3a and the rolls 3a are arranged horizontally and at the same height in the above embodiment, the pair of rolls may be arranged vertically in the vertical direction, It may be arranged diagonally in steps.

  In the above embodiment, the molten metal reservoir 4 is disposed on the cooling device 19, and the molten metal 50 stored in the molten metal reservoir 4 is supplied to the cooling device 19 for preliminary cooling and semi-solidification, and then provided between the rolls 3a. However, the molten metal 50 may be directly supplied to the cooling device 19 from the melting furnace 2 without using the molten metal reservoir 4 and may be pre-cooled and then supplied between the rolls 3a. In that case, the apparatus configuration of the continuous casting apparatus can be simplified to reduce the apparatus cost.

  In addition, although the continuous casting apparatus of the above embodiment is particularly applied to continuous casting of magnesium alloy, the continuous casting apparatus of the present invention is also suitably used for continuous casting of non-ferrous metals other than magnesium alloys or alloys thereof. .

DESCRIPTION OF SYMBOLS 1 ... Continuous casting apparatus, 2 ... Melting furnace, 3 ... Double roll, 3a ... Roll, 4 ... Molten metal storage, 9 ... Melt metal supply pipe, 19 ... Cooling device, 21 ... Cooling pipe (cooling stirring part), 50 ... Melt, 50a: Hot water surface, 50b: Hot water surface

Claims (3)

A melting furnace for melting a non-ferrous metal or its alloy;
A twin roll consisting of a pair of rolls for cooling and continuously casting a non-ferrous metal or its melt supplied from the melting furnace;
A cooling device is provided above the gap between the pair of rolls to supply a cooled material obtained by cooling the molten metal supplied from the melting furnace between the pair of rolls ,
A cylindrical molten metal reservoir for storing the molten metal is provided on the cooling device,
Between the melting furnace and the molten metal reservoir, a molten metal supply pipe for supplying the molten metal to the molten metal reservoir is provided;
The continuous casting apparatus, wherein the discharge port of the molten metal supply pipe is positioned below the surface of the molten metal stored in the molten metal reservoir .   The continuous casting apparatus according to claim 1, wherein the cooling device is formed to have a cooling / stirring portion for cooling the molten metal and stirring the molten metal by disturbing the flow of the molten metal. The continuous casting apparatus according to claim 1 or 2, wherein the non-ferrous metal or its alloy is magnesium or its alloy .

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